Struct ShellEnvironment 

pub struct ShellEnvironment { /* private fields */ }

Represents the shell variable environment, composed of a stack of scopes.

Implementations

impl ShellEnvironment

pub fn new() -> Self

Returns a new shell environment.

pub fn push_scope(&mut self, scope_type: EnvironmentScope)

Pushes a new scope of the given type onto the environment’s scope stack.

Arguments

• scope_type - The type of scope to push.

pub fn pop_scope( &mut self, expected_scope_type: EnvironmentScope, ) -> Result<(), Error>

Pops the top-most scope off the environment’s scope stack.

Arguments

• expected_scope_type - The type of scope that is expected to be atop the stack.

pub fn iter_exported(&self) -> impl Iterator<Item = (&String, &ShellVariable)>

Returns an iterator over all exported variables defined in the variable.

pub fn iter(&self) -> impl Iterator<Item = (&String, &ShellVariable)>

Returns an iterator over all the variables defined in the environment.

pub fn iter_using_policy( &self, lookup_policy: EnvironmentLookup, ) -> impl Iterator<Item = (&String, &ShellVariable)>

Returns an iterator over all the variables defined in the environment, using the given lookup policy.

Arguments

• lookup_policy - The policy to use when looking up variables.

pub fn get<S: AsRef<str>>( &self, name: S, ) -> Option<(EnvironmentScope, &ShellVariable)>

Tries to retrieve an immutable reference to the variable with the given name in the environment.

Arguments

• name - The name of the variable to retrieve.

pub fn get_mut<S: AsRef<str>>( &mut self, name: S, ) -> Option<(EnvironmentScope, &mut ShellVariable)>

Tries to retrieve a mutable reference to the variable with the given name in the environment.

Arguments

• name - The name of the variable to retrieve.

pub fn get_str<S: AsRef<str>>( &self, name: S, shell: &Shell, ) -> Option<Cow<'_, str>>

Tries to retrieve the string value of the variable with the given name in the environment.

Arguments

• name - The name of the variable to retrieve.
• shell - The shell owning the environment.

pub fn is_set<S: AsRef<str>>(&self, name: S) -> bool

Checks if a variable of the given name is set in the environment.

Arguments

• name - The name of the variable to check.

pub fn unset(&mut self, name: &str) -> Result<Option<ShellVariable>, Error>

Tries to unset the variable with the given name in the environment, returning whether or not such a variable existed.

Arguments

• name - The name of the variable to unset.

pub fn unset_index(&mut self, name: &str, index: &str) -> Result<bool, Error>

Tries to unset an array element from the environment, using the given name and element index for lookup. Returns whether or not an element was unset.

Arguments

• name - The name of the array variable to unset an element from.
• index - The index of the element to unset.

pub fn get_using_policy<N: AsRef<str>>( &self, name: N, lookup_policy: EnvironmentLookup, ) -> Option<&ShellVariable>

Tries to retrieve an immutable reference to a variable from the environment, using the given name and lookup policy.

Arguments

• name - The name of the variable to retrieve.
• lookup_policy - The policy to use when looking up the variable.

pub fn get_mut_using_policy<N: AsRef<str>>( &mut self, name: N, lookup_policy: EnvironmentLookup, ) -> Option<&mut ShellVariable>

Tries to retrieve a mutable reference to a variable from the environment, using the given name and lookup policy.

Arguments

• name - The name of the variable to retrieve.
• lookup_policy - The policy to use when looking up the variable.

pub fn update_or_add<N: Into<String>>( &mut self, name: N, value: ShellValueLiteral, updater: impl Fn(&mut ShellVariable) -> Result<(), Error>, lookup_policy: EnvironmentLookup, scope_if_creating: EnvironmentScope, ) -> Result<(), Error>

Update a variable in the environment, or add it if it doesn’t already exist.

Arguments

• name - The name of the variable to update or add.
• value - The value to assign to the variable.
• updater - A function to call to update the variable after assigning the value.
• lookup_policy - The policy to use when looking up the variable.
• scope_if_creating - The scope to create the variable in if it doesn’t already exist.

pub fn update_or_add_array_element<N: Into<String>>( &mut self, name: N, index: String, value: String, updater: impl Fn(&mut ShellVariable) -> Result<(), Error>, lookup_policy: EnvironmentLookup, scope_if_creating: EnvironmentScope, ) -> Result<(), Error>

Update an array element in the environment, or add it if it doesn’t already exist.

Arguments

• name - The name of the variable to update or add.
• index - The index of the element to update or add.
• value - The value to assign to the variable.
• updater - A function to call to update the variable after assigning the value.
• lookup_policy - The policy to use when looking up the variable.
• scope_if_creating - The scope to create the variable in if it doesn’t already exist.

pub fn add<N: Into<String>>( &mut self, name: N, var: ShellVariable, target_scope: EnvironmentScope, ) -> Result<(), Error>

Adds a variable to the environment.

Arguments

• name - The name of the variable to add.
• var - The variable to add.
• target_scope - The scope to add the variable to.

pub fn set_global<N: Into<String>>( &mut self, name: N, var: ShellVariable, ) -> Result<(), Error>

Sets a global variable in the environment.

Arguments

• name - The name of the variable to set.
• var - The variable to set.

Trait Implementations

impl Clone for ShellEnvironment

fn clone(&self) -> ShellEnvironment

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ShellEnvironment

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ShellEnvironment

fn default() -> Self

Returns the “default value” for a type.